Nitrogen-Containing Porous Carbon Fibers Prepared from Polyimide Fibers for CO₂ Capture

Abstract

Nitrogen-containing porous carbon fibers with a large BET surface area (919−1625 m 2 /g) and pore volume (0.429−0.772 cm 3 /g) were developed from polyimide fiber, which was treated in the presence of potassium carbonate by one-step simultaneous carbonization/activation. The effect of carbonization temperature on the porous and chemical structure was monitored. The nitrogen contents of activated carbon fibers decreased with the treatment temperature, which varied in a range of 1.23−2.76 wt %. Compared with the unactivated fiber, the activated ones showed more ultramicropores with a volume of more than 0.279 cm 3 /g. An optimal activated sample exhibited an excellent CO 2 uptake of 5.0 mmol/g at 1 bar and 25 °C, with an acceptable Henry's CO 2 /N 2 selectivity of 24. The ultramicropore played a predominant effect on the CO 2 uptake capacity, while the nitrogen functionalities played a predominant effect on the CO 2 /N 2 selectivity.

Nitrogen-Doped Microporous Carbon Prepared by One-Step Carbonization: Rational Design of a Polymer Precursor for Efficient CO2 Capture

“…As shown in Figure e, the low Q st of PDVA-C-600, PDVA-C-800 and PDVV-C-600 resulted in low energy loss and reduced operating costs for adsorbent regeneration. − The Q st value for PDVA-C-600 decreased slightly with CO 2 adsorption and was located between 18.3 and 20.8 kJ·mol –1 , indicating that PDVA-C-600 was dominated by the physical adsorption and the surface of PDVA-C-600 was relatively homogeneous. Similarly, the Q st of PDVA-C-800 decreased as the CO 2 load decreased in the range of 14.6–17.6 kJ·mol –1 .…”

Modulating the porosity of carbons for improved adsorption of hydrogen, carbon dioxide, and methane: a review

“…252 While KOH has been identified as a uniquely superior activating agent, its corrosive nature qualifies it as an aggressive reagent in activated carbon synthesis, thus resulting in low yields. As the majority of the microporosity comes about via the intercalation of potassium ions into graphitic layers as opposed to corrosive action of the hydroxide counterion, gentler anions such as carbonate, 232,298 and bicarbonate, 138,299 have been shown to give improved yields, resulting in high surface area carbons with tuneable porosity. For example, Sevilla and Fuertes produced KHCO 3 -activated carbons from glucose hydrochar with surface areas of 2000 m 2 g À1 with more than 80% microporosity.…”

Porous Polyimide-Based Activated Carbon Fibers for CO2 Capture and Supercapacitor

“…In previous work, we have prepared nitrogen-containing porous carbon fibers for CO 2 capture, based on polyimide fibers by synchronous carbonization/activation. 23 an ultramicropore volume of around 0.3 cm 3 /g. The activated carbon fiber showed an excellent CO 2 adsorption capacity, 6.3 mmol/g at 0 °C and 1 bar.…”

“…In previous work, we have prepared nitrogen-containing porous carbon fibers for CO 2 capture, based on polyimide fibers by synchronous carbonization/activation . K 2 CO 3 -activated carbon fibers had abundant ultramicropores, with an ultramicropore volume of around 0.3 cm 3 /g.…”